Research and analysis

Sellafield Particles in the Environment update Q1 to Q4 2021

Updated 6 June 2022

1. Progress and areas monitored

During the period 01 January to 31 December 2021 (Q1 – Q4 2021) a total area of 121 ha of the beaches along the Cumbrian coast were monitored against a programme target of 105 ha.

A total of 94 particles and 4 larger objects (1) were detected, recovered and analysed, see Table 1. The overall target for the 2021 programme is to monitor an area of 105 ha.

Further details of the programme can be found in the annual report series (2).

2. Find rates

Average find rates were compared with find rates over the last 2 calendar years in table 2 and the last 4 years in figure 1.

For clarity of presentation, the find rates in table 2 were rounded to the nearest significant figure.

Table 2 and figure 1 shows that alpha-rich particle (3), beta-rich particle and beta-rich larger object find rates at Sellafield beach and southern beaches were comparable with the average find rates from the previous years.

Alpha-rich particle find rates at northern beaches were higher than those previously measured at this area in recent years.

This increase was due to a temporary period of high find rates during Q1 2021.

Find rates in Q1 to Q4 2021 did not require any form of intervention through the Environment Agency intervention protocol (4).

3. Find activities

Figure 2 shows the activities of alpha-rich particle and beta-rich larger object finds were within the range of the activities measured since May 2014 (when the current version of the monitoring equipment was introduced).

None of the finds recovered in Q1 to Q4 2021 required characterisation through the Environment Agency characterisation protocol (4).

4. Summary of programme

Table 3 presents a summary of the beach monitoring programme since it started in 2006.

Overall, a total of 2591 ha of beaches have been monitored and 3432 particles and larger objects have been recovered and analysed.

4.1 Conclusion

The risk assessment for radioactive particles and larger objects on West Cumbrian beaches reported that:

• overall health risks for beach users are very low, and significantly lower than other risks that people accept when using the beaches.

• measures to control these risks are not warranted on public health grounds.

1. “Particles” are finds < 2 mm in diameter and “larger objects” are finds >= 2mm in diameter (includes: granules, gravel, pebbles, stones etc.)

2. Sellafield Ltd Environmental and Safety reports

3. “Alpha-rich” are finds with 241Am activity greater than 137Cs activity, “Beta-rich” are finds with 137Cs activity greater than 241Am activity and “Co-60 rich” are finds with positive 60Co activity greater than the 137Cs activity.

4. Sellafield radioactive objects interventions plan

5. UK Public Health England

5. Table 1 - Beach finds in 2021

Beach location	Area covered (ha)	No. of particles found Alpha-rich	No. of particles found Beta-rich	No. of particles found other	No. of particles found not analysed	No. of larger objects found Alpha-rich	No. of larger objects found Beta-rich	No. of larger objects found other	No. of larger objects found not analysed	Total finds
Allonby	5	0	0	0	0	0	0	0	0	0
Northern beaches	36	68	0	0	0	0	0	0	0	68
Sellafield	57	24	1	0	0	0	4	0	0	29
Southern beaches	24	1	0	0	0	0	0	0	0	1
All	121	93	1	0	0	0	4	0	0	98

Note 1: Proportion of particles as %of total finds 96 %

6. Table 2: Find per hectare and area monitored for main beach areas.

Beach location	Year	Area covered (ha)	Find category and type (finds per hectare) Alpha-rich particle	Find category and type (finds per hectare) Beta-rich particle	Find category and type (finds per hectare ) Beta-rich larger object	Find category and type (finds per hectare) other finds
Allonby	2019	10	<1	0	0	0
	2020	6	0	0	0	0
	2021	5	0	0	0	0
Northern beaches	2019	42	<1	0	0	0
	2020	30	<1	0	0	0
	2021	36	2	0	0	0
Sellafield	2019	81	<1	<0.1	<0.1	0
	2020	58	<1	<0.1	<0.1	0
	2021	57	<1	<0.1	<0.1	0
Southern beaches	2019	25	<0.1	0	0	0
	2020	19	<0.1	0	0	0
	2021	24	<0.1	0	0	0

Note 2: IA - Insufficient area coverage to estimate finds rates (<10 ha). NA - No monitoring to date. “<1” denotes values between 0.1 and 0.99. “<0.1” denotes values between zero and 0.099.

7. Table 3: Summary of beach monitoring data since programme began in 2006

Beach location	Area (ha)	Total particle	Total Larger object	Alpha-rich particle	Alpha-rich larger particle	Beta-rich particle	Beta-rich larger object	Co-60 rich particle	Co-60 larger object
Allonby	118	18	1	16	0	2	1	0	0
Northern beaches	869	867	0	810	0	51	0	6	0
Sellafield	943	1668	720	1332	6	328	712	8	2
Southern beaches	582	132	6	107	0	25	4	0	2
Other beaches	78	19	1	17	0	2	1	0	0
All	2591	2704	728	2282	6	408	718	14	4

Note: Northern beaches are St Bees and Braystones, Southern beaches are Seascale and Drigg. Allonby and Sellafield are included specifically. All other beaches (e.g. Whitehaven, Workington, Silecroft etc.) are incorporated into the “Other beaches” definition.

Note: Some Beta-rich particles have been reclassified as larger objects following analysis.

Figure 1: Find rates of Alpha-rich particles (upper), Beta-rich particles (middle) and Beta-rich larger objects (lower) between 2017 - 2021.

Note 3: Different scales used for 2021 and Synergy2 datasets.

Figure 2: Radioactivity of finds classified as alpha-rich particles (upper) and beta-rich larger objects (mid) and beta-rich particles (lower) between May 2014- December 2020 (termed Synergy2 and shown in blue) compared to data from 2021 (termed 2021 and shown in red).